Updated

Iran on Friday postponed the planned release of an American woman jailed along with two friends for more than a year, state media reported, dealing a blow to the hopes of three U.S. mothers who have pleaded for the trio's release.

Iranian officials had said that Sarah Shourd, who was detained with her friends near Iran's border with Iraq, would be released on Saturday. But the IRNA state news agency quoted the deputy chief of communication for the Iranian president's office, Mohammed Hassan Salilhimaram, as saying that would not happen.

He said details of the decision would be announced later, but Tehran's chief prosecutor, Abbas Jafari Dolatabadi, blamed the fact that "judicial procedures have not been done," according to the semiofficial ILNA news agency.

It was the latest in a series of mixed messages from Tehran in a case that has deepened tensions between the U.S. and Iran, a relationship already strained over Washington's suspicions that Tehran is trying to manufacture nuclear weapons -- something Iran denies.

Shourd and two friends, Shane Bauer and Josh Fattal, were arrested along the Iran-Iraq border in July 2009, and Tehran has accused them of illegally crossing the border and spying. Their families say they were hiking in Iraq's scenic north and that if they crossed the border, they did so unwittingly.

The U.S. State Department and relatives said they had no immediate information about the reports.

The announcement of the delay came hours after state media reported that President Mahmoud Ahmadinejad had personally intervened to secure Shourd's release in part because of the "special viewpoint of the Islamic Republic of Iran on the dignity of women."

Patrick Clawson, deputy director at the Washington Institute for Near East Policy, said the last-minute quarrels over Shroud's release highlight the internal fissures in Iran's power structure between President Mahmoud Ahmadinejad and others such as the prosecutor who could see him overreaching his authority.

"There are all kinds of internal pressures," he said. "A case like this shows there are various factions at play."

A judicial official close to the prosecutor's office said that Dolatabadi believes the release is unacceptable because Shourd should first stand before the court and then the amnesty will be granted, but not before a court hearing.

The official spoke on condition of anonymity because of the sensitive nature of the issue.

Shourd's name was not among the official list of prisoners freed at the end of Ramadan, suggesting that prosecutors want the Americans to first face trial before any kind of pardon or clemency is considered.

Typically, inmates released during Ramadan have already been convicted.

The planned release of Shourd had provided a long-sought sign of hope to the Americans' families, who have been pleading with Iranian officials to free their children since their arrest.

Now, they are once again left wondering what is going to happen.

"We don't know anything," said Samantha Topping, a New York publicist working with the families. She said the families knew only what they were hearing from media about a delayed release.